In virtually all structures which utilize incandescent lamps for lighting, a permanent installation is made into a structural wall, including ceilings, which includes a metal receptacle which is mounted to the structure and to which is connected, usually by an armored flexible conduit, to a source of electrical power.
An electrical fixture is then mounted in the receptacle and the fixture is electrically connected to the wiring in the conduit. The fixture may be mounted wholly within the receptacle, or may extend into the room and will include conventional sockets to receive screw base incandescent lamps.
The recent patent to Troy, U.S. Pat. No. 5,083,248, shows the conversion of a recessed lighting fixture to a flush mounted fixture by using the existing receptacle or junction box in combination with a flush mounted fixture which rests against the wall or ceiling and is spring coupled to the junction box. The existing electrical socket is retained in the junction box and through extenders, can be brought to a position where it can receive the bulb of the flush mounted fixture.
Currently, converting an incandescent fixture to a fluorescent fixture utilizes assemblies that are currently available with a combination of transformer, ballast and miniature fluorescent lamp. These elements are mounted on a screw base which is adapted to fit a conventional electrical lamp socket. Because of the length of the fluorescent bulb and the diameter of the socket which includes the transformer ballast combination, such assemblies have limited utility because of space limitations. For example, such assemblies cannot fit into many recessed or flush fixtures, and are too large for many applications which enclose the bulb with a decorative globe or housing.
Commercially available miniature fluorescent lamps, sometimes known as "biaxial" lamps utilizing under 20 watts can be substituted for incandescent lamps which draw 75 watts. It will be quickly appreciated that a conversion from incandescent to fluorescent lighting, if undertaken on a sufficiently large scale, can substantially reduce the demand for electrical energy and can defer the need for increases in generating capacity by several years.
Accordingly, utility companies have undertaken programs to provide incentives to encourage conversions. However, to prevent the abuse of such incentives, it is frequently a requirement that such a conversion be "hard wired" into the structure so that less costly incandescent lamps cannot be readily substituted for the fluorescent fixtures that were required.
Typically, the conversion process requires a new or different receptacle or housing that includes wiring to a fluorescent fixture assembly. The assembly includes the transformers and ballast elements required by fluorescent bulbs. Such conversions frequently require the abandonment and removal of previously installed receptacles or junction boxes which are already wired to the main power lines and to switches.
Recently, a major lamp manufacturer, General Electric, through its GE Lighting subsidiary, introduced a fluorescent lamp under the designation "GE 2 D Compact Fluorescent Lamps". Such lamps include a central base element with a planar configuration of a continuous tube formed into two, side by side, "D" shaped components.
Depending upon the wattage, at least three, different sized units have been offered. A first or 10 w unit has the dimensions of approximately 3.6" by 3.7". A second configuration, available with either 16 or 21 watts lamps has the dimensions of 5.5" by 5.5". A third configuration, available with lamps of 28 or 38 watts, has the dimensions of 8" by 8". These units can be substituted for incandescent lamps drawing 40 to 150 watts with the same illuminating efficiency.
It would be desirable to install "2 D" lamp fixtures into existing installed receptacles or junction boxes that presently house conventional incandescent fixtures without requiring extensive time consuming manual operations by skilled electricians. It would also be desirable to have a retrofit kit that can utilize either an existing incandescent lamp socket, or existing wiring after removing the socket.